Electromagnetic switching relay with permanent magnetic latch means



April 18, 1967 W, B YER ET AL 3,315,195

ELECTROMAGNETIC SWITCHING RELAY WITH PERMANENT Filed Nov. 2, 1964 MAGNETIC LATCH MEANS INVENTOKS ERIC W. BAYER WERNER MULLER ATTOR N EY 5 Sheets-Sheet 1 April 18, 1967 E. w. BAYER ET A ELECTROMAGNETIC SWITCHING RELAY WITH PERMANENT MAGNETIC LATCH MEANS Filed Nov. 2, 1964 3 Sheets-Sheet 2 FIG. IO

7 42 FIG. 9

FIG. 7

FIG. 8

INVENTORS ERIC W. BAYER M uIu WERNER MULLER ATTORNEY April 18, 1967 w BAYER ET AL 3,315,195

ELECTROMAGNETIC SWITCHING RELAY WITH PERMANENT MAGNETIC LATCH MEANS 6 Sheets-Sheet 15 Filed Nov 2', 1964 FIG. 'll

INVENTORS. ERIC W. BAYER WERNER MULLER ATTORNEY United States Patent ()fiice 3,315,1Q Patented Apr. 18, 1967 3,315,195 ELECTROMAGNETIC SWITCHING RELAY WITH PERMANENT MAGNETIC LATCH MEANS Eric W. Bayer, Woltcott, and Werner Muller, West Hartford, Conn., assignors to Allied Control Company, Inc.,

New York, N.Y., a corporation of New York Filed Nov. 2, 1964, Scr. No. 408,087 5 Claims. (Cl. 335-229) This invention relates generally to the art of electromagnetic devices and, more particularly, to an electromagnetic relay having improved features of design and construction. The invention pertains, in one of its more specific aspects, to an electromagnetic switching relay that is adapted to be readily manufactured in small and miniature sizes and that is capable of rendering efiicient and dependable service under various conditions of use.

The relay of this invention may be advantageously employed in a wide variety of environments. It is especially useful in aircrafts, missiles and related equipment which are frequently subjected to high inertia forces due to shock, vibration and continued acceleration or deceleration and in which space for operating components is limited.

The present relay successfully accomplishes multiple design objectives including (1) desirable miniaturization; (2) excellent resistance to shock, Vibration, acceleration and deceleration; (3) high operating sensitivity; (4) improved contact rating; (5) increased contact life; (6) reduction in the number of parts; (7) accurate alignment and low friction between relatively movable parts; (8) efficient and dependable operation and (9) substantial manufacturing economies.

The relay of this invention comprises several interrelated novel and improved units and means which contribute individually and collectively to the exceptional utility .of the invention. Among such units and means are an electromagnet unit consisting of a magnetizing coil and an H-shaped core assembly including a pair of offset pole piece elements; a balanced rotary armature unit consisting of a U-shaped armature, having a pair of oflset legs cooperatively associated with the pole pieces, and a switch actuator afiixed to the free ends of the armature legs; a resilient magnet unit normally maintaining the armature unit in a predetermined position; a frame unit which supports the electromagnet unit, the armature unit and the magnet unit; and connector means including a pair of stainless steel balls coupling the armature unit to the frame unit and permitting rotational or pivotal movement of the armature uni-t relative to the frame unit and the pole pieces. The steel balls and the therewith associated parts of the armature unit and the frame unit are so constructed and arranged as to attain desirable compactness, low rotational friction, long life and minimum play.

The primaly object of this invention is to provide an electromagnetic relay having improved and simplified features of design and construction.

The invention has for another object the provision of an electromagnetic rotary armature relay that is capable of being made in small and miniature sizes and that is adapted to effectively withstand shock and vibration forces and conditions of acceleration or deceleration in the course of normal use.

It is a further object of the invention to provide an electromagnetic switching relay having improved operational characteristics.

A still further object of the invention is to provide an electromagnetic relay of the character indicated that is small, compact and lightweight in design; that is sturdy and durable in construction; that is economical in manufacturing costs and that is capable of performing its intended functions in a satisfactory and reliable manner.

The relay of this invention may be advantageously employed with various types of switching arrangements including, but not limited to, single pole, double throw switches and multi-pole, double throw switches. The following detailed description and the accompanying drawings describe and illustrate, by way of example, a relay for operating a two pole, double throw switch arrangement.

In the drawings, wherein like reference characters denote corresponding parts throughout the several views:

FIG. 1 is a view in elevation of one side of a relay constructed in accordance with the invention, the cover unit of the relay being shown in cross section and a part within the confines of the cover unit being broken away for better illustration;

FIG. 2 is a View in elevation of the other side of the relay shown in FIG. 1, the cover unit and the header unit being omitted;

FIG. 3 is an end elevation view as observed from the right of FIG. 2;

FIG. 4 is a top plan view of FIG. 2;

FIG. 5 corresponds to FIG. 2 and illustrates the construction and relationship of the parts of the frame unit and the armature unit of the relay;

FIG. 6 is an end elevation view as observed from the right of FIG. 5;

FIG. 7 is a top plan view of the header unit which is also shown in other views;

FIG. 8 is a front elevation view of FIG. 7, partly in cross section for better illustration;

FIG. 9 is a top plan view of a magnet unit that is carried by the frame unit;

FIG. 10 is a front elevation view of FIG. 9; and

FIG. 11 is an exploded view of the relay on a reduced scale, the cover unit and certain parts of the header unit, which are duplicates of other parts, being omitted.

The illustrated relay consists of six principal units, namely an electromagnet unit E, a frame unit F, a magnet unit M, an armature unit A, a header unit H and a cover unit C, and a number of secondary units or parts, all of which will now be described.

Electromagnet unit E, which is best shown in FIGS. 1, 2, 3 and 11, comprises a bobbin 10 that defines a rectangular axial through opening 11 (FIG 11). The bobbin includes a pair of spaced, parallel, end flanges 12, each having a central, circular, outer recess 13 for reception of a corresponding dished spring washer 14 having a rectangular central opening 15. Wound on the bobbin is a magnetizing coil 16 which terminates in a pair of electric leads 17 and 18 (FIGS. 1 and 2). The coil is provided with an insulating outer wrapper 19.

The electromagnet unit also includes a core assembly comprising a one-piece T-shaped member 20 and a rectangular element 21 (FIG. 11). Member 20 consists of a stem element 22, which extends through washer openings 15 and bobbin opening 11, and a cross element 23. The free end of stem 22 is notched, as indicated at 24 in FIG. 11. Element 21 registers with notch 24 and is affixed to stem 22 by welding, whereby to obtain a rigid, unitary and generally H-shaped core assembly. It will be noted that elements 21 and 23 are the same in size and configuration and are offset substantially wholly to opposite sides of the longitudinal axis of stem 22. In the assembled electromagnet unit E, core elements 21 and 23 are positioned adjacent corresponding ends of the bobbin and serve as pole pieces in that they cooperate with armature unit A, as will be described, to actuate the latter upon energization of coil 16.

Frame unit F will now be described, having particular reference to FIG. 11. lower bracket 25 and an upper bracket 26. Each bracket is made of a piece of'a suitable sheet metal, suchas Thevframe unit consists of a.

stainless steel, which is cut and bent to obtain the corresponding illustrated configuration. Bracket 25 includes a horizontal wall 27, having a pair of openings 28 to receive coil leads 17 and 18, and a pair of spaced, parallel, upstanding arms 29, each of which is provided with a pair of inwardly projecting tongues 30. The central point of wall 27 is identified by a cross mark 31. Depending from the corners of wall 27 and normal to that wall are four legs 32 which terminate in corresponding feet 33. A stainless steel ball 34 is spot welded to the bottom of wall 27 at its central point 31.

Upper bracket 26 includes a horizontal wall which is parallel to wall 27. Wall 35 is cut out to form an elongated finger 36. The central point of wall 35 is identified by a cross mark 37. Positioned above and integral with wall 35 is a pair of spaced, outwardly bowed extensions 38. Bracket 26 also includes a pair of spaced legs 39 which depend from Wall 35 and which are affixed to corresponding arms 29, by welding at the time of assembly. A stainless steel ball 40, which is preferably identical with ball 34, is spot welded to the top of wall 35 at its central point 37.

Magnet unit M, which is best shown in FIGS. 4, 9, and 10, includes a pair of leaf springs 41 and 42 that bear against each other and are spotwelded together, as indicated at 43. Spring 41 is bent intermediate its ends. Spring 42 has a depending tab 44 and carries a permanent bar magnet 45 at its free end. The bar magnet may be afiixed to spring 42 in any desired manner known to the art, such as by welding. The magnet unit is secured to one end of plate extensions 38 by a spotweld that may be coincident with spotweld 43 (FIG. 4). The parts are so arranged that the free end of spring 41 presses against the end of extension 38, which is remote from spotweld 43, and tab 44 engages finger 36 to limit flexing movement of spring 42 in the direction of the other plate extension 38. The bend in spring 41 permits movement of the bar magnet and the free end of spring 42 toward the free end of spring 41.

Armature unit A comprises an inverted U-shaped armature 46 consisting of a web 47, having a semispherical indentation or recess 48 in its lower surface, and a pair of spaced depending legs 49 which are offset to opposite sides of the longitudinal center line of the web. One edge of web 47 faces bar magnet 45.

Included in the armature unit is a switch actuator Stl which comprises a planar plate 51 having a pair of oppositely projecting and relatively offset extensions 52 and a semispherical central indentation or recess 53 in its upper surface. Plate 51 spans the space between armature legs 45. Plate extensions 52 bear against and are welded to the free ends of corresponding armature legs. Integral with plate 51 is a pair of bent, downwardly projecting fingers 54 which are equi-distant from and to opposite sides of indentation 53. An insulating actuating element, such as a glass bead 55, is formed at the free end of each of these fingers.

When the relay is assembled, armature unit A is coupled to frame unit F through the medium of vertically aligned steel balls 34 and 40 which are respectively seated in actuator indentation 53 and armature indentation 48. It will be appreciated that steel balls 34 and 40 provide a low friction rotary or pivotal connection for the armature unit relative to the frame unit and the parts secured thereto. Also, the parts are so constructed and arranged that one of armature legs 49 is parallel and adjacent pole piece 21 and the other armature leg is parallel and adjacent pole piece 23. The armature is normally and yieldiugly maintained in a position away from the pole pieces by engagement of armature web 47 with bar magnet 45 (FIG. 4).

Reference is next had to FIGS. 1, 7, 8 and 11 for an understanding of the construction of header unit H. This unit comprises a base plate 56 having a plurality of notches 57 for receiving corresponding bracket feet 33 which are firmly secured thereto by spot welding, as indicated at 58 in FIG. 1. The base plate carries a plurality of fixed electrical terminals, namely terminals 59 through 62 and 59' through 62'. These terminals extend through the base plate and are firmly anchored thereto by corresponding masses of a suitable, rigid insulating material, such as glass, as indicated at 63 in FIGS. 7 and 8. Terminals 59 through 62 are equispaced and arranged in a first row. Terminals 59' through 62' are also equi-spaced, but in a somewhat different order from terminals 59 through 62, and are arranged in a second row which is parallel to the first row. Each of terminals 61 and 61 is provided with an insulating sleeve 64 (FIGS. 1 and 11) which extends through a corresponding opening 28 in bracket 25. Ter= minals 61 and 61" are respectively connected to coil leads 17 and 18 and are adapted to be connected to a suitable source of electric energy supply (not shown). Arichored to terminals 59, 62 and 59' and 62 are respective stationary contacts 69, 72, 63 and 72. These contacts are resilient, contacts 69 and 72' being generally C- shaped and contacts 72 and 69 being generally J-shaped.

The header unit also comprises a pair of movable contacts in the form of electrically conductive leaf spring contact arms 70 and 70' which are configured as best shown in FIG. 7. The contact arms are preferably made of a gold plated hardened silver-magnesium-nickel alloy to enhance their electrical characteristics and physical properties. One end of contact arm 70 is anchored by silver brazing to terminal 60 and its free end is positioned between stationary contacts 72 and 72'. Arm 70 is so configured that its free end portion normally and yieldingly engages stationary contact 72. Similarly, one en of contact arm 70' is anchored by silver brazing to ter minal 6t) and its free end portion is positioned between stationary contacts 69 and 69'. Arm 70 normally and yieldingly engages stationary contact 69'.

Contact arms 70 and 7% extend across the paths of travel of corresponding actuator beads 55. The arrangement of contact arms and actuator beads is such that, upon predetermined pivotal movement of armature unit A in one direction, arm 70 is flexed upwardly, as viewed in FIG. 7, and arm 70 is flexed downwardly, as also viewed in FIG. 7, whereby the contact arms respectively break contact with stationary contact-s 72 and 69 and make contact with stationary contacts 72 and 69.

Cover unit C is mounted on the header unit as shown in FIG. 1 and cooperates therewith to encase the parts of the relay which are located above base plate 56. The cover unit consists of a tubular side wall 73 and a top wall 74. The cover unit is open at its lower end for reception of various parts of the relay and forms a snug fit with the base plate. Bracket extensions 38 bear against opposite inner surfaces of cover wall 73 and afford additional support for parts in the upper end of the relay. These extensions, due to their resilience, effectively dampen certain shocks and vibrations to which the relay may be subjected. The cover unit is hermeti cally sealed to the base plate at the time of assembly. The cover unit may be equipped with external brackets or the like (not shown) for use in mounting the relay to a panel board or other selected location.

The operation of the herein disclosed form of the invention will now be described, it being assumed that the relay illustrate-d in the drawings is assembled and that the parts are in the relative position shown in FIG. 1 through 4. It is further assumed that magnetizing coil 16 is deenergized. Under these circumstances, armature unit A is yieldingly maintained in the position shown in FIG. 4 by engagement of armature 46 with magnet so that its arms 49 are positioned away from pole pieces 21 and 23. With the parts in the indicated relative position, actuator beads are out of engagement with corresponding contact arms 7d and When header terminals 61 and 61' are connected to a suitable source of electric energy and the magnetizing coil is energized, pole pieces 21 and 23 exert sufiicient attracting force on armature legs 49 to impart pivotal movement to the armature unit against the action of magnet 45. As a consequence, the armature unit is released from the magnet and is pivoted toward and to the extent allowed by the pole pieces. Such movement of the armature causes each actuator head 55 to engage and flex a corresponding contact arm 70 and 70', as earlier described. When a magnetizing coil is again deenergized, the parts automatically return to their original position due to the action of magnet 45.

From the foregoing, it is believed that the objects, construction and operation of our present invention will be readily comprehended by persons skilled in the art without further description. Although the invention has been herein shown and described in a simple and practicable form, it is recognized that certain parts thereof are representative of other parts which may be used in substantially the same manner to accomplish substantially the same results. Therefore, it is to be understood that the invention is not to be limited to the exact details described herein, but is to be accorded the full scope and protection of the appended claims.

We claim:

1. In an electromagnetic relay, support means, a magnetizing coil having a horizontally disposed longitudinal through opening, a core assembly comprising a central element extending through the coil opening and a pole piece at each end of the central element, each pole piece being positioned adjacent a corresponding end of the coil and secured to the support means, an armature unit comprising an inverted generally Ushaped armature including a pair of legs, each armature leg being positioned adjacent a corresponding pole piece, connector means connecting the armature unit to the support means and permitting rotary movement of the armature unit relative to the support means about a substantially vertical axis that is substantially normal to the longitudinal axis of the coil, and biasing means normally urging the armature unit in one direction of rotation relative to the support means and maintaining the armature legs in a position away from the pole pieces, the armature unit being adapted, upon energization of the coil, to be moved in a reverse direction against the action of the biasing means by magnetic attraction between the pole pieces and the armature legs, said biasing means comprising spring means including a first part secured to the support means and a second part connected to and adapted to be flexed relative to the first part, said second part being engageable by the support means whereby to limit flexing thereof relative to the support means in one direction, and a permanent magnet carried by the second part for normally engaging the armature and maintaining the armature legs in a position away from the pole pieces when the coil is deenergized.

2. An electromagnetic relay according to claim 1 wherein the armature unit comprises a web, said armature legs being offset substantially wholly to opposite sides of the longitudinal center line of the web, and a device spaced from the web and secured to the armature legs, said device being adapted to actuate a part, such as a switch element, in response to predetermined rotary movement of the armature unit relative to the support means in one direction.

3. An electromagnetic relay according to claim 1 wherein the core assembly is H-shaped, wherein the central element is rectilinear, wherein the pole pieces are offset substantially wholly to opposite sides of the longitudinal center line of the central element, wherein the armature also comprises a web and wherein the armature legs are offset substantially wholly to opposite sides of the longitudinal center line of the web.

4. An electromagnetic relay according to claim 1 wherein the support means comprises a frame unit including spaced upper and lower walls, wherein the coil is located between the walls, wherein the pole pieces are secured to the frame intermediate the walls, and wherein the connector means comprises a first member engaging the armature unit and one of the Walls and a second member engaging the armature unit and the other wall.

5. An electromagnetic relay according to claim 2 wherein the support means comprises a frame including an upper Wall positioned below the web and a lower wall spaced from the upper wall and positioned above the device, and wherein the connector means engages the web, the device and the walls.

References Cited by the Examiner UNITED STATES PATENTS 2,750,539 6/1956 Holmes 317-197 X 2,923,794 2/1960 Keeran 200-87 X 3,060,292 10/1962 Moenke 317-197 X BERNARD A. GILHEANY, Primary Examiner. H. A. LEWITTER, Assistant Examiner. 

1. IN AN ELECTROMAGNETIC RELAY, SUPPORT MEANS, A MAGNETIZING COIL HAVING A HORIZONTALLY DISPOSED LONGITUDINAL THROUGH OPENING, A CORE ASSEMBLY COMPRISING A CENTRAL ELEMENT EXTENDING THROUGH THE COIL OPENING AND A POLE PIECE AT EACH END OF THE CENTRAL ELEMENT, EACH POLE PIECE BEING POSITIONED ADJACENT A CORRESPONDING END OF THE COIL AND SECURED TO THE SUPPORT MEANS, AN ARMATURE UNIT COMPRISING AN INVERTED GENERALLY U-SHAPED ARMATURE INCLUDING A PAIR OF LEGS, EACH ARMATURE LEG BEING POSITIONED ADJACENT A CORRESPONDING POLE PIECE, CONNECTOR MEANS CONNECTING THE ARMATURE UNIT TO THE SUPPORT MEANS AND PERMITTING ROTARY MOVEMENT OF THE ARMATURE UNIT RELATIVE TO THE SUPPORT MEANS ABOUT A SUBSTANTIALLY VERTICAL AXIS THAT IS SUBSTANTIALLY NORMAL TO THE LONGITUDINAL AXIS OF THE COIL, AND BIASING MEANS NORMALLY URGING THE ARMATURE UNIT IN ONE DIRECTION OF ROTATION RELATIVE TO THE SUPPORT MEANS AND MAINTAINING THE ARMATURE LEGS IN A POSITION AWAY FROM THE POLE PIECES, THE ARMATURE UNIT BEING ADAPTED, UPON ENERGIZATION OF THE COIL, TO BE MOVED IN A REVERSE DIRECTION AGAINST THE ACTION OF THE BIASING MEANS BY MAGNETIC ATTRACTION BETWEEN THE POOL PIECES AND THE ARMATURE LEGS, SAID BIASING MEANS COMPRISING SPRING MEANS INCLUDING A FIRST PART SECURED TO THE SUPPORT MEANS AND A SECOND PART CONNECTED TO AND ADAPTED TO BE FLEXED RELATIVE TO THE FIRST PART, SAID SECOND PART BEING ENGAGEABLE BY THE SUPPORT MEANS WHEREBY TO LIMIT FLEXING THEREOF RELATIVE TO THE SUPPORT MEANS IN ONE DIRECTION, AND A PERMANENT MAGNET CARRIED BY THE SECOND PART FOR NORMALLY ENGAGING THE ARMATURE AND MAINTAINING THE ARMATURE LEGS IN A POSITION AWAY FROM THE POLE PIECES WHEN THE COIL IS DEENERGIZED. 